1. Field of Invention
The present invention is in the field of olefin oligomerization. More specifically, the present invention relates to oligomerization of olefins in the liquid phase with a nickel-containing silicaceous crystalline molecular sieve catalyst.
2. Description of the Prior Art
Oligomerization and polymerization of olefins in the gas phase over various zeolites is known in the art. For example, U.S. Pat. No. 3,960,978 a process for producing a gasoline fraction containing predominantly olefinic compounds which comprises contacting a C.sub.2 to C.sub.5 olefin with a ZSM-5 type crystalline aluminosilicate zeolite at a temperature of from about 500.degree. F. to about 900.degree. F. as disclosed.
U.S. Pat. No. 4,021,501 describes the conversion of gaseous C.sub.2 to C.sub.5 olefins into gasoline blending stock by passage over ZSM-12 at temperatures of from about 400.degree. F. to about 1200.degree. F.
U.S. Pat. No. 4,211,640 discloses a process for the treatment of highly olefinic gasoline containing at least about 50% by weight of olefins by contacting said olefinic gasoline with crystalline aluminosilicate zeolites, such as those of the ZSM-5 type, so as to selectively react olefins other than ethylene and produce both gasoline and fuel oil.
U.S. Pat. No. 4,254,295 discloses a process for the oligomerization of olefins by contacting said olefins in the liquid phase with ZSM-12 catalyst at temperatures of 80.degree. F. to 400.degree. F.
U.S. Pat. No. 4,227,992 discloses a process for separating ethylene in admixture with light olefins by contacting said olefinic mixture with a ZSM-5 catalyst and thus producing both gasoline and fuel oil range materials.
The processes disclosed in these patents differ from that of the present invention in that they employ either a different catalyst, higher temperatures, or reaction in the gaseous phase.
Also, an important feature of several of the catalysts used in these prior art processes is that the catalyst must have reduced activity before oligomerization. Such catalyst of reduced activity may be obtained by steaming or by use in a previous conversion process.
This deactivation step is not required in the process of the present invention.